Maybe I should do this, not for free stuff, but to see how they respond. My real concern is has the formula changed, and is it going to stay that way. I don't want free cookies if they are as bad as the last couple packages.
Well, there's no way the company is going to know if they're putting out a product that the consumer has issues with unless you do complain. The information you provide that comes from the packaging is recorded by the person you speak with and that in turn goes into a central database of sorts. There it can be sliced and diced in a variety of ways to determine whether there are correlations between your complaint and things like where the product was made, when it was made, raw materials, etc. I do have a couple of contacts in the food industry (competitors on a large scale are always analyzing and evaluating each other's products) and I'll make some inquiries on your behalf.
Now, there are some things that you may or may not know about the cookie and cracker industry. Formulas do change from time to time and the composition percentages of the recipe ingredients are not defined like you see written in something like your favorite one for say oatmeal/raisin cookies. The manufacture of let's say the wafers is not a perfect process. By that I mean a production run will not result in 100% perfectly shaped wafers. There will be broken ones and sundry crumbs. There will also be instances where something went awry in the baking.
So, what the manufacturers do is they gather up all these defects and use them for other purposes. Maybe they'll be sorted and sifted a particular way and be sold to ice cream manufacturers. Maybe they'll be sold to the consumer in your favorite store as toppings. And very often, they are reground and reincoroporated back into Oreos. So, when I said the formulas are not written in stone, one thing that means is that the forumulas allow for a certain percentage of regrind material. How much depends upon the nature of the regrind.
As to whether these changes can be detected by the consumer, well, sometimes. Large companies, when they're contemplating making some formulation changes actually contract with outside sources who are trained food testers. Now, besides giving the company feedback on how the modified product varies from a perfect batch, these testers are so good, and I do mean GOOD, that not only can they tell you if the product contains regrind but they can estimate how much and get this...they can tell from what factory the regrind came from!
So, complain. It's your right.